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What is the change in temperature of 2kg of water heated by a kettle using a voltage of 230V at 0.5A of current for 10 seconds? Assume no heat losses.

specific heat capacity of water, c = 4200J/kgK First student should understand that due to no heat losses the energy provided by mains socket to kettle is the same energy as the heat which changes the water ...
WS
Answered by Will S. • Physics tutor
2161 Views

How does a cyclotron work?

A cyclotron is constructed of two hollow, D-shaped electrodes that accelerate particles; they are opposite each other and there is a small gap between them. A magnetic field is used to bend the particle trac...
EM
Answered by Edward M. • Physics tutor
11157 Views

Explain the advantages of a reflecting telescope compared to a refracting telescope

Mirrors can be made much larger than lenses (meters compared to around 1m max). Mirrors do not produce chromatic aberration. Mirror glass does not need to be as high quality as lens glass. Mirrors produce le...
Answered by • Physics tutor
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A light wave has a wavelength of 420nm, calculate the energy of this wave in joules.

E = hfE = energyh = planck's constant = 6.63 x 10 -34 f = wave frequency c = fλf = c/λ E = hc/λ c = 3.0 x 10 8 The speed of light which in this case is the speed of the wave.λ = 420 x 10 -9 As 1nm = 1 x 10 -...
ND
Answered by Nicholas D. • Physics tutor
7577 Views

A 10m long uniform beam is pivoted in its centre. A 30kg point mass is placed on one end of the beam. Where must a 50kg mass be placed in order to balance the beam?

For this question, we will use moments. A moment is defined as: Moment = force x perpendicular distance from pivot Here, the moment of the 30kg mass which acts anti-clockwise through the pivot. The moment is...
JM
Answered by Joseph M. • Physics tutor
3678 Views